2010-08-30 Yao Qi <yao@codesourcery.com>

	* arm-linux-tdep.c (arm_linux_sigreturn_return_addr): New.
	(arm_linux_syscall_next_pc): New.
	(arm_linux_copy_svc): Use arm_linux_sigreturn_return_addr instead.
	(arm_linux_init_abi): Initialize syscall_next_pc.
	* arm-tdep.c (thumb_get_next_pc_raw):  Get next pc of SWI in Thumb mode.
	(arm_get_next_pc_raw): Get next pc of SWI in ARM mode.
	* arm-tdep.h (struct gdbarch_tdep): Add a function pointer syscall_next_pc.
	Declare arm_frame_is_thumb.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 4d74734f6cd786c54316b0b8d39153ef7244de38..7312034e52c91706c08340f5df67ac6c513bac4c 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,14 @@
+2010-08-30  Yao Qi  <yao@codesourcery.com>
+
+       * arm-linux-tdep.c (arm_linux_sigreturn_return_addr): New.
+       (arm_linux_syscall_next_pc): New.
+       (arm_linux_copy_svc): Use arm_linux_sigreturn_return_addr instead. 
+       (arm_linux_init_abi): Initialize syscall_next_pc.
+       * arm-tdep.c (thumb_get_next_pc_raw):  Get next pc of SWI in Thumb mode.
+       (arm_get_next_pc_raw): Get next pc of SWI in ARM mode.
+       * arm-tdep.h (struct gdbarch_tdep): Add a function pointer syscall_next_pc. 
+       Declare arm_frame_is_thumb.
+
 2010-08-30  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
        Code cleanup.

diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c
index 682054c44b4c9dfa52aa72d412be1e41628b4135..aa7d0af2b15176393a56cb060cd51b7d9929f587 100644 (file)
--- a/gdb/arm-linux-tdep.c
+++ b/gdb/arm-linux-tdep.c
@@ -630,6 +630,82 @@ arm_linux_regset_from_core_section (struct gdbarch *gdbarch,
   return NULL;
 }
 
+/* Copy the value of next pc of sigreturn and rt_sigrturn into PC,
+   and return 1.  Return 0 if it is not a rt_sigreturn/sigreturn
+   syscall.  */
+static int
+arm_linux_sigreturn_return_addr (struct frame_info *frame,
+                                unsigned long svc_number,
+                                CORE_ADDR *pc)
+{
+  /* Is this a sigreturn or rt_sigreturn syscall?  */
+  if (svc_number == 119 || svc_number == 173)
+    {
+      if (get_frame_type (frame) == SIGTRAMP_FRAME)
+       {
+         *pc = frame_unwind_caller_pc (frame);
+         return 1;
+       }
+    }
+  return 0;
+}
+
+/* When FRAME is at a syscall instruction, return the PC of the next
+   instruction to be executed.  */
+
+static CORE_ADDR
+arm_linux_syscall_next_pc (struct frame_info *frame)
+{
+  CORE_ADDR pc = get_frame_pc (frame);
+  CORE_ADDR return_addr = 0;
+  int is_thumb = arm_frame_is_thumb (frame);
+  ULONGEST svc_number = 0;
+  int is_sigreturn = 0;
+
+  if (is_thumb)
+    {
+      svc_number = get_frame_register_unsigned (frame, 7);
+    }
+  else
+    {
+      struct gdbarch *gdbarch = get_frame_arch (frame);
+      enum bfd_endian byte_order_for_code = 
+       gdbarch_byte_order_for_code (gdbarch);
+      unsigned long this_instr = 
+       read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+
+      unsigned long svc_operand = (0x00ffffff & this_instr);
+      if (svc_operand)  /* OABI.  */
+       {
+         svc_number = svc_operand - 0x900000;
+       }
+      else /* EABI.  */
+       {
+         svc_number = get_frame_register_unsigned (frame, 7);
+       }
+    }
+
+  is_sigreturn = arm_linux_sigreturn_return_addr (frame, svc_number, 
+                                                 &return_addr);
+
+  if (is_sigreturn)
+    return return_addr;
+  
+  if (is_thumb)
+    {
+      return_addr = pc + 2;
+      /* Addresses for calling Thumb functions have the bit 0 set.  */
+      return_addr |= 1;
+    }
+  else
+    {
+      return_addr = pc + 4;
+    }
+
+  return return_addr;
+}
+
+
 /* Insert a single step breakpoint at the next executed instruction.  */
 
 static int
@@ -688,8 +764,11 @@ arm_linux_copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
                    struct regcache *regs, struct displaced_step_closure *dsc)
 {
   CORE_ADDR from = dsc->insn_addr;
+  CORE_ADDR return_to = 0;
+
   struct frame_info *frame;
   unsigned int svc_number = displaced_read_reg (regs, from, 7);
+  int is_sigreturn = 0;
 
   if (debug_displaced)
     fprintf_unfiltered (gdb_stdlog, "displaced: copying Linux svc insn %.8lx\n",
@@ -697,13 +776,10 @@ arm_linux_copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
 
   frame = get_current_frame ();
 
-  /* Is this a sigreturn or rt_sigreturn syscall?  Note: these are only useful
-     for EABI.  */
-  if (svc_number == 119 || svc_number == 173)
+  is_sigreturn = arm_linux_sigreturn_return_addr(frame, svc_number,
+                                                &return_to);
+  if (is_sigreturn)
     {
-      if (get_frame_type (frame) == SIGTRAMP_FRAME)
-       {
-         CORE_ADDR return_to;
          struct symtab_and_line sal;
 
          if (debug_displaced)
@@ -711,7 +787,6 @@ arm_linux_copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
              "sigreturn/rt_sigreturn SVC call. PC in frame = %lx\n",
              (unsigned long) get_frame_pc (frame));
 
-         return_to = frame_unwind_caller_pc (frame);
          if (debug_displaced)
            fprintf_unfiltered (gdb_stdlog, "displaced: unwind pc = %lx. "
              "Setting momentary breakpoint.\n", (unsigned long) return_to);
@@ -743,7 +818,7 @@ arm_linux_copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
       else if (debug_displaced)
        fprintf_unfiltered (gdb_stdlog, "displaced: sigreturn/rt_sigreturn "
                            "SVC call not in signal trampoline frame\n");
-    }
+    
 
   /* Preparation: If we detect sigreturn, set momentary breakpoint at resume
                  location, else nothing.
@@ -946,6 +1021,9 @@ arm_linux_init_abi (struct gdbarch_info info,
   set_gdbarch_displaced_step_free_closure (gdbarch,
                                           simple_displaced_step_free_closure);
   set_gdbarch_displaced_step_location (gdbarch, displaced_step_at_entry_point);
+
+
+  tdep->syscall_next_pc = arm_linux_syscall_next_pc;
 }
 
 /* Provide a prototype to silence -Wmissing-prototypes.  */

diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 5a7e76d711ac54cd838e299556dbbf3181fca780..4a028c8385cbff750d760162d5cc9e6ad26375e8 100644 (file)
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -270,7 +270,7 @@ arm_psr_thumb_bit (struct gdbarch *gdbarch)
 
 /* Determine if FRAME is executing in Thumb mode.  */
 
-static int
+int
 arm_frame_is_thumb (struct frame_info *frame)
 {
   CORE_ADDR cpsr;
@@ -2828,7 +2828,16 @@ thumb_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt)
   else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
     {
       unsigned long cond = bits (inst1, 8, 11);
-      if (cond != 0x0f && condition_true (cond, status))    /* 0x0f = SWI */
+      if (cond == 0x0f)  /* 0x0f = SWI */
+       {
+         struct gdbarch_tdep *tdep;
+         tdep = gdbarch_tdep (gdbarch);
+
+         if (tdep->syscall_next_pc != NULL)
+           nextpc = tdep->syscall_next_pc (frame);
+
+       }
+      else if (cond != 0x0f && condition_true (cond, status))
        nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
     }
   else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
@@ -3277,7 +3286,16 @@ arm_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt)
        case 0xc:
        case 0xd:
        case 0xe:               /* coproc ops */
+         break;
        case 0xf:               /* SWI */
+         {
+           struct gdbarch_tdep *tdep;
+           tdep = gdbarch_tdep (gdbarch);
+
+           if (tdep->syscall_next_pc != NULL)
+             nextpc = tdep->syscall_next_pc (frame);
+
+         }
          break;
 
        default:

diff --git a/gdb/arm-tdep.h b/gdb/arm-tdep.h
index 87387aabb64cfac84c04b951549abe71f9123710..61cdb5d5eacd7504024d7a500e725bf52a0b034d 100644 (file)
--- a/gdb/arm-tdep.h
+++ b/gdb/arm-tdep.h
@@ -196,6 +196,10 @@ struct gdbarch_tdep
   struct type *arm_ext_type;
   struct type *neon_double_type;
   struct type *neon_quad_type;
+
+  /* Return the expected next PC if FRAME is stopped at a syscall
+     instruction.  */
+  CORE_ADDR (*syscall_next_pc) (struct frame_info *frame);
 };
 
 /* Structures used for displaced stepping.  */
@@ -297,6 +301,7 @@ extern void
 CORE_ADDR arm_skip_stub (struct frame_info *, CORE_ADDR);
 CORE_ADDR arm_get_next_pc (struct frame_info *, CORE_ADDR);
 int arm_software_single_step (struct frame_info *);
+int arm_frame_is_thumb (struct frame_info *frame);
 
 extern struct displaced_step_closure *
   arm_displaced_step_copy_insn (struct gdbarch *, CORE_ADDR, CORE_ADDR,